In case that an electronic product has the multimedia playing function, the electronic product is usually equipped with an audio chip. The audio chip outputs audio signals to a speaker through an output stage circuit. Once the supplied power is suddenly interrupted during the process of switching off the electronic product, the residual charges of the output stage circuit are possibly transmitted to the speaker. Under this circumstance, the pop noise is generated. The pop sound is unpleasant to the hearing of the user.
Therefore, it is important to provide an approach for avoiding the pop noise when the supplied power is suddenly interrupted.